Swampfire by Patricia Cecil Haas, TK2870, 1st Scholastic paperback printing, 1974, 187 pages. Illustrated by Charles Robinson.
DESCRIPTION: “‘Swampfire!’ It was a perfect name for the great, beautiful horse. Sally, Robin, and Andrew had discovered in the marshes. But now, the name means a raging fire which can destroy everything and everyone in the swamp.
Here at last is Sally’s chance to ride the beautiful ghost-horse in the swamp. Can she do it- and rescue the trapped victims?” (from the back cover)